For some commercial and industrial applications, conveyorized microwave ovens have advantages over batch type microwave ovens. One advantage is that conveyor systems generally have higher throughput. Another advantage is that automatic loading and unloading equipment is more readily adaptable to conveyor systems. Accordingly, there is wide spread usage of conveyorized microwave ovens.
One common application for conveyorized microwave ovens is food processing. For this application, varying amounts of microwave exposure may be necessary for different cooking tasks. For example, equivalent weights of bacon and meat patties may require different amounts of energy to cook. Also, for a particular food type such as bacon, varying amounts of BTUs may be required depending on the initial and final states of the cooking task. More specifically, the initial state may be frozen, refrigerator temperature, or room temperature. The final state may be precooked or fully cooked. Precooked may be defined as cooking out grease until the product weighs 40% of its initial weight; fully cooked may be when the final product weighs 30% of its initial weight.
It is only under the most ideal and rare combination of parameters that two different food types may be simultaneously cooked to their respective desired donenesses. Also, it is apparent that the same food type can not be simultaneously processed from different initial states nor to different final states. Accordingly, in prior art conveyorized microwave ovens, the line is shut down and the power of the oven or speed of the belt is changed to switch from one cooking task to another. This procedure reduces system throughput and creates scheduling problems.